Idea to Sketch to 3D Print to Plaster Mold
ฝัง
- เผยแพร่เมื่อ 22 พ.ย. 2024
- Shape Cast: shapecastmolds...
Want to go from an idea of a pot to a custom plaster slip casting mold? Here I walk through the process of starting with an idea, designing the profile, using Shape Cast to create 3D printable models for plaster, assembling the 3d printed mold, pouring plaster, and slip casting a pot in the new custom mold!
TOOLS and MATERIALS (affiliate)
Calipers amzn.to/4dXKT4l
PLA+ amzn.to/3QrWnnt
Filler Primer amzn.to/3P69Yye
220 sand paper amzn.to/4bYyNX2
CA glue and activator amzn.to/3x6fkEK
M3x8 screws amzn.to/3qensjc
M3 threaded inserts amzn.to/3OrJl6W
Driver amzn.to/44TsHDY
Foam Gasket amzn.to/44X7IAf
Soldering Station amzn.to/3KnlBiM
Diamond sanding pads (120 & 200) amzn.to/3P6Awj0
Razor Blade amzn.to/3Kpfydn
Drill Attachment Mixer amzn.to/3OP9iiv
Spigot amzn.to/3u4t95n
Motorcycle lift amzn.to/3unWK9M
Step drill set amzn.to/49gXOLp
Socket amzn.to/49dJ2VX
Socket adapter amzn.to/3vX3Tys
Buckets amzn.to/49eCupX
Bucket lids amzn.to/42jbljn
Knife amzn.to/3Opr2jv
I made my first mold from Shapecast a few weeks ago. I can say, without pause, if you can print in ABS or ASA - do it! I could acetone weld the pieces and then do a very light vapor smoothing for the center plug. The finish quality of the mold is better than when I used to mold existing objects/glasses.
That's great to hear!
@@PotterybyKent I have spent the last two days refining my second mold form in Shapecast and was wondering if there might be a way to have the system generate the final mold as three parts-the bottom and center plug as a single item and then the two outer shells. Also, is there a way to export the center plug so that the flange that holds the threaded inserts does not create a cavity that requires support? If not, depending on how the forms are generated (I would assume some version of OpenSCAD), can the files be exported in .step or a similar format to allow for easier post-export modifications (I am playing with the idea of cutting out a small shallow "trench" to insert 1.75mm TPU filament like an O-ring gasket - something I have done with small epoxy molds in the past)?
I ended up taking the STLs for the center plug and two bottom halves and throwing them into Windows 3D Builder so I could merge them together along with a custom solid to fill that tiny gap/shelf in the center plug and screw holes that were no longer needed. However, since working with an STL with thousands of triangles, the end merge was a bit "dirty."
The short version is no, that's not possible right now with the way the code is set up.
The cold alcohol trick to shrink the PLA was something I haven’t seen before.
It works really well! Before that I had struggled many times getting the print to come out of the plaster.
For the areas that need more filling (like the bottom) try spot putty (it's like a toothpaste version of filler primer) just put it on , use something smooth to spread it out and smooth as best as possible, let dry 30 minutes and sand, then you can use a single coat of the filler primer if needed (to hide the sanding marks).
Thanks for the tip!
Awesome stuff, really enjoyed this guide :)
That's great to hear!
Kent great vid. Thanks.
After the piece is dried out completelly in bone phase how much time do I have until burn it? Can I leave the piece for like months in bone stage? I’m asking because I don’t have an oven yet but I want to start making ceramics. Thank you!
Yes they can be left bone dry for a long time. They're very fragile so easy to break but that's about all. You'd also probably want to keep the dust off but anything organic would burn off in the kiln
Hi, Kents, great technical video! I was also wondering, after you dry out your plaster molds, do you use anything to seal it from crumbling or leaving stains on the table? I just notice that after some time of using my old molds their bottoms starts to leave plaster stains on my worktable and their corners starts to crumble a bit. My molds are not new they are quite old and the sides are very well preserved and feels smooth while their bottoms are soft and fragile. Thank you!
No, I don't treat mine in any way. In general the molds are meant to be consumable - they will wear out over time. So I just make new ones as needed (pour plaster in the 3d print again). The hardness of the plaster comes down to the plaster type. For slip casting a softer plaster is actually beneficial. It's not so much about being soft as it is about having a high porosity (lots of tiny holes) to absorb the water. Some people make their molds out of different plaster which is stringer, but the tradeoff is the mold is much much slower. I'm not exactly sure what might cause a difference between different sides of the same mold without knowing more about how it was made.
@@PotterybyKent thank you for your answer and sorry for mistyping your name :)
I made my molds in the old fashioned way, I put my master in a small bucket upside down and then I poured the plaster all the way up. As a result what is the top in the bucket is my mold's bottom and since it haven't been treated with any oil or wax it always becomes a bit different comparing to the sides which had contact with bucket and its oiled sides. I do not treat the final mold but I always oil my buckets sides with coconut oil (:D) what makes easy to separate plaster from the bucket - as a result all sides become very nicely treated apart cthe bottom. I always wondered what proffesionals do and how they treat their molds since this is my way and not sure if it makes sense. Thanks!
I pour mine the same way - upside down - so that the bubbles rise from the surface. One guess is that your oil is interacting with the plaster in some way (do you wash it out after the plaster is cured?). It might also be the way your mixing the plaster so that the top is more fragile. But those are both really just guesses.
Some people will refine the plaster once it is mostly set (eg smooth it out with a rasp, knife or the like). That could deal with any unevenness on that face of the mold. If there are sharp corners - those are often more prone to breaking so rounding everything off can help.
@@PotterybyKent Thanks Kent. I think you are right. Sometimes when I do make them I see that after the plaster starts to get thicker it pushes all the water to the top of the bucket. The plaster becomes strong but there are still some water on the top. Thats how I know that I probably failed with my proportions so I just pour the water from the top away and leave it to dry. That might be the reason too.
From the other hand, I am starting to think that maybe there is nothing wrong with a bottom - just the sides became super strong after interacting with oil :D and thats why the bottom feels so fragile in comparison. I wash my molds after I make them but just with a sponge and quickly, feels that oil is well absorbed by the plaster and I can't wash it away much :)
Thanks a lot from your insights, very helpful and interesting to discuss about these topics with someone :)
Ah, the plaster definitely should not separate like that when wet. That is why it is weaker and would be the root cause of your issue (and that is unrelated to the oil).
This is a brilliant integration of modern maker tech and the ancient craft of ceramics. I have an architecture background but I teach ceramics in a high school. I'm looking forward to incorporating these ideas into our workflow next year for my intermediate/advanced class. I love the idea of 3D printing a master mold, so that I can have my students make multiple copies of the plaster molds for the entire class to use. One question I have is: have you tried using mold bands with your 3D printed pieces, with a gasket in place of course, rather than the threaded inserts and bolts, if so, how did it work? Just thinking about the time and budget I have for mold making. Thank you for these great videos and for shapecast!
Glad to hear that! I tried several things to close up the outer mold. I've used foil tape in the past with success but I find it a pain. If you want to go slow and steady - caulking is also ok. You just need to wait for it to cure. The threaded inserts actually go pretty fast, are cheap, and are good insurance against a plaster disaster. With mold bands, you wouldn't be able to securing down the inner mold (and I'm not sure they'd work for the outer without leaking).
Hi Kent, thanks for the cool workflow demo!
Have you tried printing TPU gaskets?
Happy to share! TPU could work, but I haven't used it. One of the things I was originally considering was just a rubber gasket (o-ring style) however I didn't go down that path since the tolerances would need to be tighter. The gasket works remarkably well for keeping the plaster helps back.
This was extremely helpful! Is Shapecast still accepting new users?
It is indeed!
@@PotterybyKent I printed the larger tumbler with the 1 piece outter shell, rather than printing 4 pieces. Is there a way to remove the 3d print from the plaster? I got the middle piece out with the ice water alcohol combo, but I'm wondering if it would work if I heated up the outter part. I'm thinking a towel soaked in hot water? I totally forgot to add Murphy's wash on the inside.
That is exactly why the outer mold is multiple pieces. In early development I ended up cutting them off. I doubt hot water would do too much. And mold release really isn't needed since this isn't a plaster on plaster pour.
I'm becoming addicted to isopropyl alcohol.
It makes it so easy!
@@PotterybyKent Yes this idea is as great as it is simple.